Hydrangea plant named ‘Hortmablo’

ABSTRACT

A new and distinct cultivar of  Hydrangea  plant named ‘Hortmablo’, characterized by its upright to broadly spreading plant habit; moderately vigorous to vigorous growth habit and moderate to rapid growth rate; freely branching habit with strong and thick sturdy stems; relatively large leaves; mophead-type inflorescences with large light pink-colored sterile flowers; and good postproduction longevity.

Botanical designation: Hydrangea macrophylla.

Cultivar denomination: ‘HORTMABLO’.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct cultivar ofHydrangea plant, botanically known as Hydrangea macrophylla,commercially referred to as a mophead-type Hydrangea and hereinafterreferred to by the name ‘Hortmablo’.

The new Hydrangea plant is a product of a planned breeding programconducted by the Inventor in Boskoop, The Netherlands. The objective ofthe breeding program was to create new Hydrangea plants with largeinflorescences with numerous and attractive sterile flowers and goodpostproduction longevity.

The new Hydrangea plant originated from a cross-pollination made by theInventor on Jun. 2, 2010 in Boskoop, The Netherlands, of a proprietaryselection of Hydrangea macrophylla identified as code number 08-038-06,not patented, as the female, or seed, parent with Hydrangea macrophylla‘Snowball’, not patented, as the male, or pollen, parent. The newHydrangea plant was discovered and selected by the Inventor as a singleflowering plant from within the progeny of the stated cross-pollinationin a controlled greenhouse environment in Boskoop, The Netherlands inJuly, 2014.

Asexual reproduction of the new Hydrangea plant by vegetative terminalcuttings in a controlled environment in Boskoop, The Netherlands hasshown that the unique features of this new Hydrangea plant are stableand reproduced true to type in successive generations.

SUMMARY OF THE INVENTION

Plants of the new Hydrangea have not been observed under all possiblecombinations of environmental conditions and cultural practices. Thephenotype may vary somewhat with variations in environmental conditionssuch as temperature and light intensity without, however, any variancein genotype.

The following traits have been repeatedly observed and are determined tobe the unique characteristics of ‘Hortmablo’. These characteristics incombination distinguish ‘Hortmablo’ as a new and distinct Hydrangeaplant:

-   -   1. Upright to broadly spreading plant habit.    -   2. Moderately vigorous to vigorous growth habit and moderate to        rapid growth rate.    -   3. Freely branching habit with strong and thick sturdy stems.    -   4. Relatively large leaves.    -   5. Mophead-type inflorescences with large light pink-colored        sterile flowers.    -   6. Good postproduction longevity.

Plants of the new Hydrangea can be compared to plants of the femaleparent selection. Plants of the new Hydrangea differ primarily fromplants of the female parent selection in sterile flower color as sterileflower sepals of plants of the female parent selection are darker incolor than sterile flower sepals of plants of the new Hydrangea. Inaddition, plants of the new Hydrangea have larger leaves and sterileflower sepals than plants of the female parent selection.

Plants of the new Hydrangea can be compared to plants of the maleparent, ‘Snowball’. Plants of the new Hydrangea differ primarily fromplants of ‘Snowball’ in sterile flower color as plants of ‘Snowball’have white-colored sterile flower sepals. In addition, inflorescences ofplants of the new Hydrangea are more flattened than and not as globularas inflorescences of plants of ‘Snowball’.

Plants of the new Hydrangea can be compared to plants of the Hydrangeamacrophylla ‘Hokomathyst’, disclosed in U.S. Plant Pat. No. 22,261. Inside-by-side comparisons plants of the new Hydrangea differ primarilyfrom plants of ‘Hokomathyst’ in the following characteristics:

-   -   1. Plants of the new Hydrangea have larger leaves than plants of        ‘Hokomathyst’.    -   2. Plants of the new Hydrangea have larger sterile flower sepals        than plants of ‘Hokomathyst’.    -   3. Plants of the new Hydrangea and ‘Hokomathyst’ differ in        sterile flower color as plants of ‘Hokomathyst’ have red        purple-colored sterile flower sepals with green-colored margins.

Plants of the new Hydrangea can also be compared to plants of theHydrangea macrophylla ‘Hortmasnodo’, not patented. In side-by-sidecomparisons plants of the new Hydrangea differ primarily from plants of‘Hortmasnodo’ in sterile flower color as plants of ‘Hortmasnodo’ havesterile flower sepals that are white in color.

BRIEF DESCRIPTION OF THE PHOTOGRAPHS

The accompanying colored photographs illustrate the unique appearance ofthe new Hydrangea plant showing the colors as true as it is reasonablypossible to obtain in colored reproductions of this type. Colors in thephotographs may differ from the color values cited in the detailedbotanical description which accurately describe the colors of the newHydrangea plant.

The photograph on the first sheet is a side perspective view of atypical flowering plant of ‘Hortmablo’.

The photograph on the second sheet is a close-up view of a typicalinflorescence of ‘Hortmablo’.

DETAILED BOTANICAL DESCRIPTION

Plants used in the aforementioned photographs and in the followingdescription were grown during the late spring in 17-cm containers in aglass-covered greenhouse in Boskoop, The Netherlands and under culturalpractices typical of commercial Hydrangea production. During theproduction of the plants, day temperatures ranged from 18° C. to 25° C.and night temperatures ranged from 16° C. to 17° C. Plants of the newHydrangea were two years old when the photographs and description weretaken. Plants of the new Hydrangea are not typically treated withaluminum sulfate to “blue” the inflorescences. In the followingdescription, color references are made to The Royal HorticulturalSociety Colour Chart, 2015 Edition, except where general terms ofordinary dictionary significance are used.

-   Botanical description: Hydrangea macrophylla ‘Hortmablo’.-   Parentage:    -   -   Female, or seed, parent.—Proprietary selection of Hydrangea            macrophylla identified as code number 08-038-06, not            patented.        -   Male, or pollen, parent.—Hydrangea macrophylla ‘Snowball’,            not patented.-   Propagation:    -   -   Type cutting.—By vegetative terminal cuttings.        -   Time to initiate roots, summer.—About three weeks at            temperatures about 15° C. to 25° C.        -   Time to produce a rooted young plant, summer.—About six            weeks at temperatures about 15° C. to 25° C.        -   Root description.—Medium in thickness, fibrous; typically            creamy white in color, actual color of the roots is            dependent on substrate composition, water quality,            fertilizer type and formulation, substrate temperature and            physiological age of roots.        -   Rooting habit.—Moderately freely branching; medium density.-   Plant description:    -   -   Plant and growth habit.—Upright and broadly spreading plant            habit; overall plant shape is flattened globular; strong and            sturdy lateral branches; moderate to rapid growth rate and            moderately vigorous to vigorous growth habit.        -   Plant height.—About 55 cm.        -   Plant diameter or area of spread.—About 68.5 cm.-   Lateral branch description:    -   -   Branching habit.—Freely branching habit; when pinched, about            ten lateral branches develop per plant.        -   Length.—About 30.9 cm.        -   Diameter.—About 8 mm.        -   Internode length.—About 9.2 cm.        -   Texture.—Smooth, glabrous; fully developed, woody.        -   Aspect.—Upright to about 30° from vertical.        -   Strength.—Strong, sturdy.        -   Color.—When developing: Close to 144B. Developed: Close to            144A to 144B; at the internodes, tinged with close to N186C;            when woody, close to 199C and 200D.        -   Lenticels.—Density: Moderate to dense. Length: About 2.5 mm.            Diameter: About 0.5 mm. Color: Close to N186C.-   Leaf description:    -   -   Arrangement.—Opposite, simple.        -   Length.—About 15.3 cm.        -   Width.—About 10.4 cm.        -   Shape.—Broadly elliptic to broadly ovate.        -   Apex.—Apiculate.        -   Base.—Short attenuate.        -   Margin.—Serrate.        -   Texture, upper surface.—Smooth to slightly rugose, glabrous.        -   Texture, lower surface.—Smooth to slightly rugose, surface            mostly glabrous, however small tufts of short hairs present            at vein axils.        -   Venation pattern.—Pinnate.        -   Color.—Developing leaves, upper surface: Close to 144A.            Developing leaves, lower surface: Close to 144B. Fully            expanded leaves, upper surface: Close to 137A; venation,            close to 145A to 145B. Fully expanded leaves, lower surface:            Close to 144A; venation, close to 145B.        -   Petioles.—Length: About 2.8 cm. Diameter: About 5 mm.            Texture and luster, upper and lower surfaces: Smooth,            glabrous; slightly glossy. Color, upper surface: Close to            145B; towards the margins, close to 144B. Color, lower            surface: Close to 145A.-   Flower description:    -   -   Flower type and habit.—Showy sterile flowers and small            inconspicuous fertile flowers arranged on mophead-type            terminal panicles; panicles globular and slightly flattened            in shape; fertile flowers face mostly upright and sterile            flowers face upright to outwardly and slightly drooping            depending on their position in the inflorescence.        -   Fragrance.—None detected.        -   Natural flowering season.—Plants flower from late spring to            late summer in The Netherlands.        -   Flower longevity.—Fertile flowers last about five days on            the plant, fertile flowers not persistent; sterile flowers            last about six weeks on the plant, sterile flowers            persistent.        -   Quantity of flowers.—Freely flowering habit; about 20            fertile flowers per panicle and about 120 sterile flowers            per panicle.        -   Panicle height.—About 11.5 cm.        -   Panicle diameter.—About 17.9 cm.        -   Fertile flower buds.—Length: About 4 mm. Diameter: About            4 mm. Shape: Obovate. Color: Close to NN155B; towards the            base, close to 145B to 145C.        -   Sterile flower buds.—Length: About 3 mm. Diameter: About            3.5 mm. Shape: Flattened globular. Color: Close to 69B to            69C.        -   Fertile flower diameter.—About 1.2 cm.        -   Fertile flower depth (height).—About 9 mm.        -   Sterile flower diameter.—About 5.5 cm.        -   Sterile flower depth (height).—About 2.4 cm.        -   Petals, fertile flowers.—Quantity and arrangement: Four or            occasionally five in a single whorl. Length: About 6 mm.            Width: About 3 mm. Shape: Ovate, concave. Apex: Acute. Base:            Cuneate. Margin: Entire. Texture and luster, upper and lower            surfaces: Smooth, glabrous; matte. Color: When opening and            fully opened, upper surface: Close to 155C. When opening and            fully opened, lower surface: Close to 155C; towards the            base, close to NN155D.        -   Petals, sterile flowers.—Quantity and arrangement: About            four or occasionally five in a single whorl. Length: About            4 mm. Width: About 3 mm. Shape: Ovate, concave. Apex: Acute.            Base: Cuneate. Margin: Entire. Texture and luster, upper and            lower surfaces: Smooth, glabrous; matte. Color: When            opening, upper surface: Close to 75D; towards the margins,            close to NN155D. When opening, lower surface: Close to            NN155A; towards the apex, tinged with close to 75D. Fully            opened, upper surface: Close to NN155A; slightly tinged with            close to 75D. Fully opened, lower surface: Close to NN155A;            towards the apex, slightly tinged with close to 75D.        -   Sepals, fertile flowers.—Quantity and arrangement: Five or            occasionally six in a single whorl. Length: About 2 mm.            Width: About 1.5 mm. Shape: Ovate. Apex: Acute. Base:            Broadly cuneate. Margin: Entire. Texture and luster, upper            and lower surfaces: Smooth, glabrous; matte. Color: When            opening, upper and lower surfaces: Close to between 150D and            155A. Fully opened, upper and lower surfaces: Close to            between 150D and 155A; color does not change with            development.        -   Sepals, sterile flowers.—Quantity and arrangement: Four in a            single whorl. Length: About 2.8 cm. Width: About 3.9 cm.            Shape: Roughly reniform. Apex: Emarginate, praemorse. Base:            Cuneate. Margin: Crenate. Texture and luster, upper and            lower surfaces: Smooth, glabrous; matte. Color: When            opening, upper and lower surfaces: Close to NN155D;            distally, tinged with close to 69D. Fully opened, upper            surface: Close to 69B; towards the base, close to 65B to            65C; color becoming closer to 145B with development. Fully            opened, lower surface: Close to 69B; venation, close to 65B;            color becoming closer to 145C with development.        -   Pedicels, fertile flowers.—Length: About 2 mm. Diameter:            About 1 mm. Strength: Moderately strong. Aspect: About 20°            from vertical. Texture and luster: Moderately to densely            pubescent; matte. Color: Close to 65D.        -   Pedicels, sterile flowers.—Length: About 2.2 cm. Diameter:            About 2 mm. Strength: Moderately strong. Aspect: About 45°            from vertical. Texture and luster: Moderately pubescent;            matte. Color: Close to N155B.        -   Reproductive organs, fertile flowers.—Stamens: Quantity per            flower: About ten. Filament length: About 5.5 mm. Filament            color: Close to NN155D. Anther length: About 1 mm. Anther            shape: Oblong. Anther color: Close to 157D. Pollen amount:            Moderate. Pollen color: Close to 159D. Pistils: Pistil            quantity per flower: About three or four. Pistil length:            About 1 mm. Stigma shape: Club-shaped. Stigma color: Close            to NN155D. Style length: About 0.5 mm. Style color: Close to            NN155B. Ovary color: Close to between 150D and 155A.        -   Reproductive organs, sterile flowers.—Stamens: Quantity per            flower: About eight. Filament length: About 2.5 mm. Filament            color: Close to NN155C. Anther length: About 1 mm. Anther            shape: Oblong. Anther color: Close to 155A. Pollen amount:            Moderate. Pollen color: Close to 159D. Pistils: Pistil            quantity per flower: About three or four. Pistil length:            About 1 mm. Stigma shape: Club-shaped. Stigma color: Close            to NN155A. Style length: About 1 mm. Style color: Close to            NN155A. Ovary color: Close to 145D.        -   Seeds.—Seed development has not been observed on plants of            the new Hydrangea to date.-   Disease & pest resistance: Under commercial production conditions,    plants of the new Hydrangea have not been observed to be resistant    to pathogens and pests common to Hydrangea plants.-   Temperature tolerance: Plants of the new Hydrangea have been shown    to be suitable for USDA Hardiness Zones 5 to 9.

It is claimed:
 1. A new and distinct Hydrangea plant named ‘Hortmablo’ as illustrated and described. 